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secondary 3 | E Maths
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Please help me with 3b. Thank you ㋛
Date Posted: 3 years ago
Views: 151
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Since the ratio of interior to exterior angle for the given pair is 7 : 3 and we know a pair of interior + its corresponding exterior angle = 180°,(angle sum on a straight line)
Exterior angle = 180° × 3/(3+7)
= 180° × 3/10 = 54°
Next, for any polygon, sum of exterior angles = 360°
If the polygon is regular, all its exterior angles will be equal, and so will be 54°.
We would be able to divide 360° equally by the exterior angle of 54° to get a whole number/integer . This is the number of sides the polygon has.
But, 360°÷ 54° = 6⅔, which is not a whole number/integer.
So the polygon is not regular since we can't get an exact number of sides with 54° for each exterior angle.
Exterior angle = 180° × 3/(3+7)
= 180° × 3/10 = 54°
Next, for any polygon, sum of exterior angles = 360°
If the polygon is regular, all its exterior angles will be equal, and so will be 54°.
We would be able to divide 360° equally by the exterior angle of 54° to get a whole number/integer . This is the number of sides the polygon has.
But, 360°÷ 54° = 6⅔, which is not a whole number/integer.
So the polygon is not regular since we can't get an exact number of sides with 54° for each exterior angle.
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